Rhodamine, thio-rhodamine, acridine, and carbopyronin compounds of the formula ##STR00001## wherein M is either (1) a metal ion having a positive charge of +y wherein y is an integer which is at least 2, said metal ion being capable of forming a compound with at least two ##STR00002## chromogen moieties, or (2) a metal-containing moiety capable of forming a compound with at least two chromogen moieties, z is an integer representing the number of chromogen moieties associated with the metal and is at least 2, R.sub.1, R.sub.2, R.sub.3, R.sub.4, R.sub.5, R.sub.6, R.sub.7, a, b, c, d, Y, and z are as defined herein, Q.sup.- is a COO.sup.- group or a SO.sub.3.sup.- group, A is an organic anion, and CA is either a hydrogen atom or a cation associated with all but one of the Q.sup.- groups.